PaperMC/patches/server/0417-Do-not-let-the-server-load-chunks-from-newer-version.patch
Owen 89d51d5f29
Allow enabling sand duping (#10191)
Because this exploit has been widely known for years and has not been fixed by Mojang, we decided that it was worth allowing people to toggle it on/off due to how easy it is to make it configurable.

It should be noted that this decision does not promise all future exploits will be configurable.
2024-03-03 17:05:34 -05:00

41 lines
2.6 KiB
Diff

From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
From: Zach Brown <zach@zachbr.io>
Date: Tue, 23 Jul 2019 20:44:47 -0500
Subject: [PATCH] Do not let the server load chunks from newer versions
If the server attempts to load a chunk generated by a newer version of
the game, immediately stop the server to prevent data corruption.
You can override this functionality at your own peril.
diff --git a/src/main/java/net/minecraft/world/level/chunk/storage/ChunkSerializer.java b/src/main/java/net/minecraft/world/level/chunk/storage/ChunkSerializer.java
index cbc8e95c8f890f0c0eb717d4d2ae3f427dc260d8..3b046dc106b96b7ca2b148d605e8b7c97453d033 100644
--- a/src/main/java/net/minecraft/world/level/chunk/storage/ChunkSerializer.java
+++ b/src/main/java/net/minecraft/world/level/chunk/storage/ChunkSerializer.java
@@ -84,6 +84,10 @@ public class ChunkSerializer {
public static final String BLOCK_LIGHT_TAG = "BlockLight";
public static final String SKY_LIGHT_TAG = "SkyLight";
+ // Paper start - Do not let the server load chunks from newer versions
+ private static final int CURRENT_DATA_VERSION = net.minecraft.SharedConstants.getCurrentVersion().getDataVersion().getVersion();
+ private static final boolean JUST_CORRUPT_IT = Boolean.getBoolean("Paper.ignoreWorldDataVersion");
+ // Paper end - Do not let the server load chunks from newer versions
public ChunkSerializer() {}
// Paper start - guard against serializing mismatching coordinates
@@ -99,6 +103,15 @@ public class ChunkSerializer {
}
// Paper end - guard against serializing mismatching coordinates
public static ProtoChunk read(ServerLevel world, PoiManager poiStorage, ChunkPos chunkPos, CompoundTag nbt) {
+ // Paper start - Do not let the server load chunks from newer versions
+ if (nbt.contains("DataVersion", net.minecraft.nbt.Tag.TAG_ANY_NUMERIC)) {
+ final int dataVersion = nbt.getInt("DataVersion");
+ if (!JUST_CORRUPT_IT && dataVersion > CURRENT_DATA_VERSION) {
+ new RuntimeException("Server attempted to load chunk saved with newer version of minecraft! " + dataVersion + " > " + CURRENT_DATA_VERSION).printStackTrace();
+ System.exit(1);
+ }
+ }
+ // Paper end - Do not let the server load chunks from newer versions
ChunkPos chunkcoordintpair1 = new ChunkPos(nbt.getInt("xPos"), nbt.getInt("zPos")); // Paper - guard against serializing mismatching coordinates; diff on change, see ChunkSerializer#getChunkCoordinate
if (!Objects.equals(chunkPos, chunkcoordintpair1)) {